Vinews

No. 2 — Feb. 22, 2021

Contents:

• Primary Bud Mortality of Selected Cultivars

Primary Bud Mortality of Selected Cultivars

On Monday Feb. 22, 2021, cane samples were collected from four different vineyard blocks in the vicinity of Hermann, Mo. Approximately 50 buds were evaluated for each sample on Feb. 24-25. Two samples of Vignoles had the greatest bud damage (Table 1). As I mentioned in the previous report, a number of factors play a role in bud mortality, including location. Bud mortality of Vignoles was 5% and Chambourcin was 18% at the Missouri State Fruit Station in Mountain Grove, Mo (Table 2). Almost the exact opposite results compared to Gasconade County. Wright county (Mountain Grove, MO) did experience lower temperatures compared to the east-central area where Gasconade and Franklin counties are located (Figure 3). The bud mortality data from Mountain Grove suggests that growers should definitely determine bud mortality of Chardonel and Vidal blanc.

In summary, from this limited data set from Gasconade, Franklin and Wright counties the below zero temperatures that occurred on Feb. 13-16, 2021, resulted in very limited damage to grape buds.

Table 1. Primary bud mortality of selected grape cultivars from four different vineyard blocks located in Gasconade and Franklin counties, Missouri.

Table 2. Primary bud mortality of selected grape cultivars at the Mountain Grove Fruit Station in Wright County, MO. Data supplied by Marilyn Odneal